Conventional golf balls can be divided into two general classes: solid and wound. Solid golf balls include one-piece, two-piece (i.e., solid core and a cover), and multi-layer (i.e., solid core of one or more layers and/or a cover of one or more layers) golf balls. Wound golf balls typically include a solid, hollow, or fluid-filled center, surrounded by a tensioned elastomeric material, and a cover. Solid balls have traditionally been considered longer and more durable than wound balls, but also lack a particular “feel” provided by the wound construction.
By altering ball construction and composition, manufacturers can vary a wide range of playing characteristics, such as compression, velocity, and spin, each of which can be optimized for various playing abilities. One golf ball component, in particular, that many manufacturers are continually looking to improve is the center or core. The core becomes the “engine” of the golf ball when hit with a club head. Generally, golf ball cores and/or centers are constructed with a polybutadiene-based polymer composition. Compositions of this type are constantly being altered in an effort to provide a higher coefficient of restitution (“COR”) while at the same time resulting in a lower compression which, in turn, can lower the golf ball spin rate, provide better “feel,” or both. This is a difficult task, however, given the physical limitations of currently-available polymers. As such, there remains a need for novel and improved golf ball core compositions.
It has been determined that, upon addition of a halogenated organosulfur compound or the salts thereof, in particular, pentachlorothiophenol (“PCTP”) salt, to polybutadiene rubber compositions, that golf ball cores may be constructed that exhibit increased COR, decreased compression, or both. The present invention is, therefore, directed to golf ball centers and cores that include a halogenated organosulfur compound, or a salt thereof, for embodiments such as these.